1. Field of the Invention
This invention relates broadly to surgical instruments. More particularly, this invention relates to biopsy forceps intended to be inserted through an endoscope or used in laparoscopic procedures.
2. State of the Art
Biopsy forceps are generally inserted through an endoscope and used to obtain tissue samples from within the body. It is often necessary to obtain a tissue sample from the wall or side of a biological lumen such as the esophagus. When using a conventional end-viewing endoscope, the distal end of the scope must be turned to the side to aim the instrument in the direction of the tissue to be sampled. However, the esophagus is quite narrow, making maneuvering of the endoscope within the lumen of the esophagus quite difficult. Although a side-viewing endoscope can be used to obtain an esophageal biopsy, the scope is nearly useless in examining the stomach which is also typically done in a procedure in which esophageal samples are desired, thus necessitating both an end-viewing endoscope and a side-viewing endoscope for a single procedure.
Accordingly, several biopsy forceps or similar devices have been described which enable deflection of the distal end of the biopsy forceps without requiring bending of the distal end of the endoscope. Such maneuvering permits samples to be taken off-axis from the endoscope lumen; i.e., xe2x80x9ctangentialxe2x80x9d sampling.
For example, U.S. Pat. No. 5,715,832 to Koblish et al. discloses a deflectable biopsy forceps which utilizes a catheter-like shaft and a deflection wire coupled to the distal end of the shaft and extending along the length of the shaft. A pair of biopsy jaws are also coupled to the distal end of the shaft. When the deflection wire is tensioned, the shaft bends in the direction of the tension to direct the jaws radially and eventually up to 180xc2x0.
Another biopsy forceps device is disclosed in U.S. Pat. No. 5,386,818 to Schneebaum et al. The distal end of the Schneebaum device is spring biased to have a tendency to form an arcuate configuration. When the distal end of the device is substantially within the lumen of the endoscope, the biopsy jaws are directed substantially axially with the lumen of the endoscope. However, as the distal end is advanced from the lumen of the endoscope, an increasingly larger arcuate shape is provided.
U.S. Pat. No. 4,880,015 to Nierman discloses yet another biopsy forceps purportedly capable of tangential sampling. The biopsy forceps device has a hinge at a distal end thereof, and a jaw assembly is coupled to the device distal of the hinge. The jaw assembly is adapted to pivot, and thereby articulate, in one direction about the hinge to move the jaw assembly relative to the longitudinal axis of the device.
While each of the above described devices may have the ability to controllably deflect or bend to some degree or another, there is nevertheless no way to direct the deflection to sample a tissue at a particular location about the inner surface of the biological lumen. This is because the known devices are only capable of deflection in a single direction. That is, in the direction of the tension (Koblish et al.), the direction of the spring bias (Schneebaum), or the direction of pivot about a hinge (Nierman).
In addition, the desired direction of deflection cannot even be obtained by rotating the entire biopsy forceps within the lumen of the endoscope, due to the inability of the construct of biopsy forceps, in general, to controllably transmit rotational force, i.e., torque, along their relatively long lengths.
It is therefore an object of the invention to provide a biopsy forceps instrument which is optimized to sample esophageal tissue or tissue along the length of another biological lumen.
It is another object of the invention to provide a biopsy forceps instrument adapted to sample tissue at any rotational location about an end of the instrument and the end of an endoscope through which the instrument extends.
It is a further object of the invention to provide a biopsy forceps instrument having a deflectable end which can be controlled to move in any direction about the end of the instrument and the end of the endoscope.
It is an additional object of the invention to provide a biopsy forceps instrument which has a deflectable end and a rotatable jaw assembly.
In accord with these objects, which will be discussed in detail below, an endoscopic or laparoscopic biopsy forceps instrument is provided which includes a flexible tubular member having proximal and distal ends, a biopsy jaw assembly at the distal end of the tubular member, actuation means to operate the jaw assembly between open and closed positions, deflection means to deflect the biopsy jaw assembly relative to an endoscopic or laparoscopic lumen through which the instrument extends, and rotation means to rotate the distal end of the tubular member and jaw assembly about its longitudinal axis.
An endoscopic or laparoscopic biopsy forceps instrument is provided which includes a flexible tubular member having proximal and distal ends, a biopsy jaw assembly at the distal end of the tubular member, an actuation assembly to operate the jaw assembly between open and closed positions, and a control assembly to deflect the biopsy jaw assembly relative to a lumen through which the instrument extends and to rotate the jaw assembly about the longitudinal axis of the instrument.
According to a first embodiment, an actuation handle, e.g., of the conventional shaft and spool type, is provided to open and close the jaw assembly, and a control handle, preferably of ball and socket configuration, operates to direct (i.e., both rotate and move angularly relative to the longitudinal axis AL of the instrument) the jaw assembly via control wires coupled at one end to the ball and at the other end to the clevis of the jaw assembly such that tangential biting by the jaw assembly is facilitated. In the first embodiment, the jaws assembly includes two jaws positionable about the clevis, which in turn is rotatable relative to a coil. Actuation wires running from the actuation handle to the tangs of each jaw permit opening and closing of the jaw.
According to a second embodiment similar to the first embodiment, the jaw assembly includes two jaws, preferably made from a shape memory material and coupled together at their proximal ends, and a sleeve. Movement of the jaws relative to the sleeve, e.g., via coupling the proximal ends of the jaws to the actuation wire and fixing the sleeve at the distal end of the tubular member, operates to open and close the jaw assembly.
According to a third embodiment of the invention, the jaw assembly includes a proximal portion and a distal portion spring-biased relative to the proximal portion and thereby adapted to be deflected at a desired angle relative to the longitudinal axis of the instrument. However, the bias may be overcome when the instrument is forced through or withdrawn from an endoscope or lumen smaller than the radial extension of the distal portion of the jaw assembly. An actuation means is provided for operating the jaws, and a rotation control means is provided for rotating the jaw assembly.
According to fourth embodiment, the jaw assembly includes a flexible tube, a clevis terminating in a stationary jaw, and a jaw pivotably coupled to the clevis and thereby movable between open and closed positions relative to the stationary jaw. A proximal actuation means is provided to cause the movement. The flexible tube is preferably made from nitinol or another shape memory material, and preferably includes a plurality of slots oriented transverse the longitudinal axis of the tube which, under compressive force, are adapted to form the tube into a curved configuration. Once the compressive force is released, the shape memory property of the nitinol urges the tube back towards a linear configuration. A deflection wire in conjunction with the proximal actuation means is adapted to provide compressive force to the tube. In addition, a means is also provided to rotate the tube and the jaw assembly of the instrument.
In each of the embodiments, a biopsy forceps instrument is provided in which the jaw assembly is deflected or deflectable, the jaw assembly can be rotated about the longitudinal axis of the instrument, and the jaws can be operated to open and close to take a biopsy sample.
Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.